HOT-PRESSED THICK-SHEET STEEL, PRODUCT MOULDED BY STAMPING, AND METHOD OF MANUFACTURING PRODUCTS MOULDED BY STAMPING Russian patent published in 2017 - IPC C22C38/60 C22C38/14 C21D9/46 C21D1/18 B21D22/20 

FIELD: metallurgy.

SUBSTANCE: steel contains, wt %: C: 0.15 to 0.5, Si: 0.2 to 3, Mn: 0.5 to 3, P: 0.05 or less (except 0), S: 0.05 or less (except 0), Al: 0.01 to 1, B: of 0.0002 to 0.01, N: 0.001 to 0.01%, Ti: in the amount equal to or greater than 3.4[N]0.01% and equal to or less than 3.4[N]0.1%, where [N] is the content (wt %) N, the rest are iron and unavoidable impurities. The average diameter of the equivalent circle of Ti-containing inclusions having an equivalent circle diameter of 30 nm or less among the Ti-containing inclusions contained in the steel sheet is 3 nm or more. The amount of Ti in the inclusions and the total amount of Ti in the steel satisfy the ratio: (the amount of Ti in the inclusions (wt %)-3.4[N])≥0.5×[(total amount of Ti (wt %))-3.4[N]], where [N] is the content (wt %) N in the steel. The share of ferrite in the metallographic microstructure is 30% or more.

EFFECT: required balance between high strength and elasticity is provided.

6 cl, 1 dwg, 16 tbl, 2 ex